Towing rear sag question

Discussion in 'Towing' started by Some Guy with a GM, Aug 18, 2018.

  1. Some Guy with a GM

    Some Guy with a GM Newbie

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    Hi,

    One more quick question:

    1998 Tahoe 1/2 ton + 2100lbs (2600lbs-ish loaded) 18ft trailer. The rear end sags by about 1 3/4" and you can notice it when looking at it. Mind you, the rear sags almost as much when I stand on the rear bumper. I just took it on a long trip and it behaved well - no sway, steering braking seemed normal including during some nasty mountain climbs and decents.

    Given my circumstances...

    1. just leave it be as it is working
    2. look at upgrading the rear springs?
    3. appropriate weight distribution hitch?

    Thanks,
    Chris
     
  2. Supercharged111

    Supercharged111 I'm Awesome

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    Not heavy enough for WD. Measure how far the front rises too, is it a visual thing that concerns you or does it buck and heave?
     
  3. Some Guy with a GM

    Some Guy with a GM Newbie

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    Thanks,

    Drives fine - visual thing. The front (measured gap between top of tire and bottom of wheel arch/fender) is about 1" increase.
     
  4. Supercharged111

    Supercharged111 I'm Awesome

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    That front raise makes it look worse than it is. You could do a 1" zero rate add a leaf from ORD. Or try one of those cheapo half leaves they sell at Autozone that bolt right on.
     
  5. 1997

    1997 Newbie

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    #3 is the way to go, lots of advantages beside adjusting right height.
     
  6. Some Guy with a GM

    Some Guy with a GM Newbie

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    Here is a pic - increased gap above front tires is 1", and rear sags about 1 3/4". Too much? Truck is stock.

    [​IMG]
     
  7. 95C1500

    95C1500 ┌П┐(◣_◢)┌П┐

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    You could look into some air bags. I think one day mine will get a set
     
    Bob L likes this.
  8. Fez_Jet_Az

    Fez_Jet_Az Newbie

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    You have a fine dance there... Think about your Family and the Motoring Public...

    Look at your weight ratings for the rear axle on your drivers side door.

    Then load up truck with gas, all the crap that you will stuff in the rear and on the roof, add your Family or Friends that would travel with you, hook your camper as you would load it to go out for the weekend.

    Then find a truck stop with a scale. Scale out twice, usually you get a free re weigh for the fee of the scale and sometimes its a couple dollars more.
    1. scale your rig as full ready with camper, all 3 axles, 1 axle per pad at the scale
    2. scale out with your camper dropped off in the parking lot, just weigh your truck, 1 axle per pad.

    This will give you some numbers to do some math with. You will discover first if you are exceeding your rear axle weight rating which typically is the combined max of the factory tire size ratings at max pressure. You will also discover what the tongue weight of your camper is by subtracting the rear axle scale value with the camper dropped in the parking lot from the rear axle scale value with the camper hooked up.

    If you are exceeding your max rear axle rating without the camper attached you have problems to start. If you are exceeding your max rear axle rating with the camper attached then you also have problems but possible solutions with a weight distribution hitch. Adding a weight distribution hitch presents a second possible problem in over loading the axle on the camper as it will shift weight forward in the tow vehicle to the front axle as well as backward to the camper axle, that function of physics is how it get weight off the rear axle, by loading it forward and back to the leading and trailing axles.

    If you find that you are exceeding your rear axle rating you are great risk as what that tells you is you are exceeding the capacity of your tires and might explode one. If you explode a truck tire while towing it threatens the lives of all in your vehicle as well as the vehicles near you as you will lose control, I have been there and done that an exploded a rear axle tire at 65-70mph in my suburban with 10,000lbs hooked up, it was literally the grace of God that let us walk away with our lives and no major damage. Why did I explode a tire? Well I had slightly oversize BFG all terains on my factory wheels and after the incident I came to find that rim width did not meet the minimum width for the tire size and likely blew it up due heat generated from excessive sidewall flex. But who actaully knows, that was before I nearly died and became a compulsive freak about what I tow and how my weight is distributed.

    AIR BAGS WILL NEVER EVER EVER EVER EVER EVER FIX AN OVERLOADED AXLE.......PERIOD.......all they will do is mask any sag you have, go to a scale and get your weights.

    You like Me tow with an SUV and not a pickup truck, that gives us an incredible disadvantage to start as that much of our GVWR is already eaten up by the extra metal, glass, carpet, seats, etc... that is built into the platform. By looking at your picture I bet you are already exceeding the 500lb non distribution rating on your hitch as it appears you have dual propane tanks and batteries.

    Wreck your rig while towing in excess of your component rating and you can bet your arse your insurance company will deny your claim, they train their claims adjusters to investigate these details. Wreck your rig while towing in excess of your component rating and you can bet your arse that if you injure someone and they get a lawyer you will have a civil suit brought against you for reckless endangerment.

    The rest is up to you. Take a guess, make a hunch, or go get some numbers to determine if that axle sag is OK or NOT...

     
    Last edited: Aug 23, 2018
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  9. Some Guy with a GM

    Some Guy with a GM Newbie

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    Hi,

    Thanks for the reply. The only part I'm not clear on is:

    "You will discover first if you are exceeding your rear axle weight rating which typically is the combined max of the factory tire size ratings at max pressure."

    My rear axle is 3700lbs and the tires are each rated are 2400lbs max.
     
  10. Supercharged111

    Supercharged111 I'm Awesome

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    SRW 3/4 and 1 tons were rated to 6k out back. 3000 sounds about right for a rinky dink 215 or 225 stock sized tire.
     

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